Neumann boundary condition (i.e., constant derivative)
warning The value passed must not be the value of the derivative.
Instead, it must be comprehensive of the grid step
between the first two points--i.e., it must be the
difference between f[0] and f[1].
todo generalize to time-dependent conditions.
Neumann boundary condition (i.e., constant derivative) warning The value passed must not be the value of the derivative. Instead, it must be comprehensive of the grid step between the first two points--i.e., it must be the difference between f[0] and f[1]. todo generalize to time-dependent conditions.